Motorized drapery puller tensioning means



Jan. 14, 1964 o, McLEAN ETAL 3,117,767

MOTORIZED DRAPERY FULLER TENSIONING MEANS Filed July 6, 1961 2 Sheets-Sheet 1 [hi 62760215. James (2 McZean, MW/am A. Pea/ 7776/)" A 25 tar/15y.

Jan. 14, 1964 J. o. MCLEAN ETAL MOTORIZED DRAPERY FULLER TENSIONING MEANS Filed July 6, 1961 2 Sheets-Sheet 2 Fig. 3

United States Patent 3,117,767 MQTGF'ZEE DRAPERY suntan rENsroNnsG MEANE Earner. t). McLean, Milford, and William A. Peslalr, Fairfield, Conn, assignors to General Electric Company, a corporation of New York Filed Euly 6, 1961, Ser. No. 122,312 2 Claims. (11. zs4 r75.s

This invention relates to a motorized drapery puller which automatically opens and closes draperies, curtains, or the like and more specifically to an improved means for maintaining the proper tension on the drapery cord moved by the drapery puller.

Motorized drapery pullers, which are known in the prior art, generally operate by having the motor driven pulley engage a looped drapery cord to thereby move the cord causing the drapes to open or close. In order for the drapery puller to operate satisfactorily it is essential that the slippage between the drapery cord and the pulley be minim zed so that the drapes are actuated smoothly and quickly. Therefore, it is necessary to maintain proper tension on the drapery cord with respect to the pulley and to maintain a positive frictional engagement between the cord and the pulley. Further, the pulley should be designed to prevent knotting of the drapery cord to insure reliable operation.

It is a basic object of the invention to provide an im proved drapery puller which operates smoothly and dependably.

It is an important object of the invention to provide an improved tensioning means for a motorized drapery puller.

it is a further object of the invention to provide an improved pulley for a motorized drapery puller.

Briefly stated, the invention relates to a drapery puller including a bracket adapted to be fixed to a wall, a casing supporting a motor and pulley arrangement, a plurality of guides fixed to the bracket for positioning the casing, and a bead chain connecting the casing and the lower end of the bracket. A portion of the casing is formed with two parallel slides and the guides are arranged on the bracket to form a pair of trackways for receiving the slides so that the casing, including the motor and pulley may be slidably moved vertically with respect to the bracket. The head chain is attached to the casing and may be connected to the lower end of the bracket to maintain the desired tension on the drapery cord to be driven by the pulley. The pulley comprises two substantially identical outer segments made of a hard smooth material having a low coefficient of friction and a cylindrical center section made of a material having a high coeflicient of friction. The outer segments each have a tapered surface positioned at an angle with respect to the center section so that the drapery cord will be kept in positive frictional engagement with the center section and encounters only negligible friction along the surfaces of the outer segments.

Further features, objects and advantages will become apparent with reference to the following specification and drawings in which:

FIG. 1 is a perspective view of a motorized drapery puller incorporating the invention;

H6. 2 is a rear view of the motorized drapery puller without the supporting wall bracket; and

FIG. 3 is a side view of the motorized drapery puller incorporating the invention showing the casing and wall bracket in cross-section.

Referring to the drawings, PEG. 1 shows a preferred embodiment of a motorized drapery puller 1t? comprising an elongated casing 11 and a rectangular wall bracket "ice 12. The casing 11 supports a motor driven pulley 13 which engages a looped drapery cord (not shown) which is passed through an opening 14 in a top flange 15' of the casing 11. The casing 11 is supported by the drapery cord when the cord is engaging the pulley 13 and is guided on the wall bracket 12, as will be described hereinafter.

The wall bracket 12 is shown as a channel shaped portion 16 having a pair of extending flanges 17 and 18. The back portion of the channel member 16 is adapted to be positioned on a wall or window frame in the vicinity of the draper cord, and attached to the wall by means of suitable fastening means extending through any of the plurality of slots 19 formed in channel member 16. A plurality of guides 29, $1, 22 and 23 are attached to the bracket 12; more specifically, guides 29 and 21 are shown attached to flange l7 and guides 22 and 23 are shown attached to flange 18. Each of the guides 29-2 3 is provided with a slot, as shown for example at 2:4- in guide Zll; and the guides are arranged and positioned on the flanges 17 and 18 so that the slots in the guides provide two parallel trackways. The rear portion of the casing 11 has two inwardly extending flanges 25 and 26, which form two parallel slides to slide within the track ways formed by the slots in the guides fill-23. In addition to providing a trackway for casing 11, the guides ill-23 absorb the torque reaction caused by the rotation of pulley 13. The guides 2ll-23 may be made of any suitable material, but are preferably of nylon or similar material having a low coefficient of friction without the application of grease, being durable, and not producing irritating noises when moved in contact with the flanges 25 and 26 of casing 11.

The top flange 15 limits movement of casing 11 to prevent it from falling to the floor in the event the drapery cord should break or should become disengaged from the pulley 13. Also, when the bracket 12 is not attached to the wall, the flange '15 prevents the casing from being disengaged from bracket 12 if carried in the vertical position, thus making the entire unit ll convenient to handle.

The pulley 13 may be driven by any suitable motor; the preferred embodiment shown by FIGS. 2 and 3 cmploys a capacitor type motor 3% connected to a gear box 31. through which torque is transmitted to the pulley 13. The gear box 31 is shown attached to the front wall of the casing by suitable studs 32. Three conductors 33, shown by HQ. 2, connect the capacitor motor 39-, a source of current and a suitable switch means such as a pair of pushbuttons, one of which is shown at 34.

The casing 11 and its attached components provide a certain amount of tension of the drapery cord which engages pulley 13. However, to provide additional tension and to make the amount of tension adjustable, the casing 11 should be connected to the support bracket 12 in some manner other than by means of the nylon guides 294,3. For this purpose, a plate 35 is provided which extends horizontally across the casing 11 and to which is fastened one end of a bead chain 36, as shown by FIG. 3. The opposite end of head chain 36 cooperates with a keyhole slot 37 in a bottom flange 33 which extends forwardly from the lower end of channel portion 16 of wall bracket 1.2. The dimensions of the keyhole 37, are, of course, selected so that the larger dimension is large enough to permit passage of the beads of chain 36, while the smaller dimension is smaller than the beads whereby the chain may be adjustably secured to plate 38. By pulling the casing 11 downwardly and then locking the chain 36 in position by means of the keyhole slot 37, the desired tension on the drapery cord may be obtained. This arrangement has been found to be extremely easy to operate while yet providing the needed adjustability and reliability.

Although the tensioning means tends to prevent slippage between the drapery cord and the pulley 13, it is also desirable to utilize the pulley arrangement of the invention in order to obtain reliable operation. In its preferred form, FIG. 3, pulley 13 comprises a pair of substantially identical outer segments 4&1 and 41 and a cylindrical center section 42. The segments 4t and 41 are made of a hard smooth material having a low coefficient of friction and each have a tapered surface positioned at an angle with respect to center section 42, which is made of a material having a high coeflicient of friction. With such an arrangement, the drapery cord looped on pulley 13 is kept in engagement with the center section 4% by which it is frictionally driven while encountering only negligible friction along the surfaces of the outer segments 40 and 41. Furthermore, it has been found that the most satisfactory operation is obtained when the center section 42 is only slightly wider than the combined widths of the two or three loops of the drapery cord which is to be wound thereon. As the pulley 13 rotates, the drapery cord tends to move sideways in a screw thread action, but the lack of friction with the tapered sides of the segments 4% and 41 force at least one loop of the cord to stay on the center section 42 at all times to provide the proper contact. The slippery tapered surfaces of the segments 4!} and 41 also prevent knots from forming in the cord and, in conjunction with the bead chain 36 tensioning device, prevent the cord from jumping off the pulley 13.

The mounting and operating procedure of the preferred form of the motorized drape puller of the invention will now be summarized to complete the understanding of the invention. First, a suitable wall surface should be chosen for mounting the bracket 12 thereon in a vertical position so that the guides 2 l'23 form two vertical trackways. The drapery cord should then be adjusted to form a loop in the proper place so that the cord can be passed through the opening 14 in top flange 15 and looped two or three times around the pulley 13. While pulling down on the casing 11 to tension the drapery cord, the position of the casing 11 may be marked on the mounting surface to indicate the proper position for fixing bracket 12 to the wall surface. After fixing bracet 12 to the wall, the casing 11 may then be inserted into the guides Zil-23, and the bead chain 36 inserted in the keyhole slot 37 of the flange 38. The casing 11 should then be pulled vertically downward to the desired position and the bead chain 36 attached to the bottom flange 38 by means of slot 37 to maintain the desired tension.

The drape puller should now be ready to operate. De-

pressing one of the pushbuttons 34 commences rotation of the pulley 13, and the friction force between the pulley 13 and the drapery cord causes the cord and attached drapes to be moved in an opening or closing direction depending upon which pushbutton is depressed. If the drapery cord slips on the pulley 13, the casing 11 may be moved further downwardly and locked in the new position by the bead chain 36.

The particular embodiment described is merely an example of the invention, and it will be obvious to those skilled in the art that various changes and modifications may be made without departing from the invention in its broader aspect. Therefore it is intended in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What we claim is:

1. In a drapery puller comprising (A) a bracket adapted to be attached to a wall,

(3) a casing vertically slideable with respect to said bracket,

(1) a pulley supported by said casing for driving engagement with a drapery cord, and

(2) a motor supported by said casing for driving said pulley;

(C) means for varying the relative position of said casing and said bracket to vary the tension on said cord, said means including (1) a plate extending laterally from the lower end of said bracket, and

(2) a pull member attached to and extending down- Wardly from said casing,

(3) said pull member being arranged to selectively engage said plate in any of a plurality of positions for varying the relative position of said casing and bracket and thereby the tension on said cord.

2. In a drapery puller comprising (A) a bracket adapted to be attached to a wall,

(B) a casing vertically slideable with respect to said bracket,

(1) a pulley supported by said casing for driving engagement with a drapery cord, and

(2) a motor supported by said casing for driving said pulley;

(C) means for varying the relative position of said casing and said bracket to vary the tension on said cord, said means including (1) a plate extending laterally from the lower end of said bracket,

(2) said plate having a slot therein and (3) a bead chain having a plurality of spaced apart heads,

(4) said bead chain being attached to, and extending downwardly from said casing,

(5) said head chain being arranged so that any of said beads may be selectively engaged with said plate adjacent said slot for varying the relative position of said casing and bracket and thereby the tension on said cord.

References Cited in the file of this patent UNITED STATES PATENTS 334,998 Wardwell Ian. 26, 1886 2,187,846 Williams Jan. 23, 1940 2,788,481 Lui et al Apr. 9, 1957 2,798,194 Cantin July 2, 1957 FOREIGN PATENTS 546,770 Belgium Apr. 30, 1956 

1. IN A DRAPERY PULLER COMPRISING (A) A BRACKET ADAPTED TO BE ATTACHED TO A WALL, (B) A CASING VERTICALLY SLIDEABLE WITH RESPECT TO SAID BRACKET, (1) A PULLEY SUPPORTED BY SAID CASING FOR DRIVING ENGAGEMENT WITH A DRAPERY CORD, AND (2) A MOTOR SUPPORTED BY SAID CASING FOR DRIVING SAID PULLEY; (C) MEANS FOR VARYING THE RELATIVE POSITION OF SAID CASING AND SAID BRACKET TO VARY THE TENSION ON SAID CORD, SAID MEANS INCLUDING (1) A PLATE EXTENDING LATERALLY FROM THE LOWER END OF SAID BRACKET, AND (2) A PULL MEMBER ATTACHED TO AND EXTENDING DOWNWARDLY FROM SAID CASING, (3) SAID PULL MEMBER BEING ARRANGED TO SELECTIVELY ENGAGE SAID PLATE IN ANY OF A PLURALITY OF POSITIONS FOR VARYING THE RELATIVE POSITION OF SAID CASING AND BRACKET AND THEREBY THE TENSION ON SAID CORD. 